Sticky panels on a desktop web app. Conventions and debate

Is anyone aware of current debate or conventions on the use of sticky headers/footers in web apps?

I'm designing a screen for trading investments. This is an inherently complex task for most users. Steering them to the next activity with an obvious CTA is quite difficult given how much the user has to see. I'm experimenting with a sticky footer to hold a summary of the users trade instructions with an obvious 'submit trade' button.

Has anyone got any good links to examples of this done well?